1240786-97-3Relevant academic research and scientific papers
Synthesis of a Dimeric Base-Stabilized Cobaltosilylene Complex for Catalytic C?H Bond Functionalization and C?C Bond Formation
Khoo, Sabrina,Cao, Jiajia,Yang, Ming-Chung,Shan, Yu-Liang,Su, Ming-Der,So, Cheuk-Wai
, p. 14329 - 14334 (2018)
The synthesis of a dimeric base-stabilized cobaltosilylene complex and its catalytic reactions are described. Treatment of the amidinato silicon(I) dimer [LSi:]2 (1; L=PhC(NtBu)2) with CoBr2 in toluene for 10 days afforded the dimeric amidinato cobaltosilylene [(LSi)μ-{CoBr(LSiBr)}]2 (2), which is speculated to proceed via “LSiCoBr” and “LSiBr” intermediates in the reaction. Compound 2 is paramagnetic, with an effective magnetic moment of 2.8 μB. Its electronic structure was elucidated by single-crystal X-ray crystallography and DFT studies. It was capable of catalyzing C?H bond functionalization, in which a combination of 2, phosphine and MeMgI can regio- and stereoselectively promoted the addition of the C≡C triple bonds in alkynes to the ortho-C?H position in arylpyridines. In addition, compound 2 catalyzed Kumada-type coupling reactions between aryl chlorides and the Grignard reagent 2-mesitylmagnesium bromide.
Cobalt-catalyzed hydroarylation of alkynes through chelation-assisted C-H bond activation
Gao, Ke,Lee, Pin-Sheng,Fujita, Takeshi,Yoshikai, Naohiko
supporting information; experimental part, p. 12249 - 12251 (2010/11/18)
Ternary catalytic systems consisting of cobalt salts, phosphine ligands, and Grignard reagents promote addition of arylpyridines and imines to unactivated internal alkynes with high regio- and stereoselectivities. Deuterium-labeling experiments suggest that the reaction involves chelation-assisted oxidative addition of the aryl C-H bond to the cobalt center and insertion of the C-C triple bond into the Co-H bond, followed by reductive elimination of the resulting diorganocobalt species.
